A talk given at the Wordpress London meetup about version control, Git, and how to most effectively use Git with WordPress.

1. Developing with
WordPress and Git
Rob Miller • @robmil
Big Fish Design
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2. An introduction
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3. “Git”? Huh?
What’s that?
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4. “Git”? Huh?
What’s that?
• A distributed version control system
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5. “Git”? Huh?
What’s that?
• A distributed version control system
• Free
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6. “Git”? Huh?
What’s that?
• A distributed version control system
• Free
• Open source
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7. “Git”? Huh?
What’s that?
• A distributed version control system
• Free
• Open source
• Popular
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8. A crash course in
version control
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9. What is
version control?
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10. What is
version control?
• Track changes made to source code
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11. What is
version control?
• Track changes made to source code
• Who did what and when
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12. What is
version control?
• Track changes made to source code
• Who did what and when
• When things break, revert to the point
when it last worked
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13. What is
version control?
• Track changes made to source code
• Who did what and when
• When things break, revert to the point
when it last worked
• Like Time Machine for your website’s
code (but not database/content…)
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14. Why version control?
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15. Why version control?
• “I just deleted a file by mistake — can we get
it back?”
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16. Why version control?
• “I just deleted a file by mistake — can we get
it back?”
• “I need to know who made this change —
can we find out?”
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17. Why version control?
• “I just deleted a file by mistake — can we get
it back?”
• “I need to know who made this change —
can we find out?”
• “That feature just broke the site — can we
revert it?”
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18. Why version control?
• “I just deleted a file by mistake — can we get
it back?”
• “I need to know who made this change —
can we find out?”
• “That feature just broke the site — can we
revert it?”
• “There’s a bug that didn’t use to exist. When
was it introduced?”
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19. Centralised
vs. distributed
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20. Centralised
version control
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21. Centralised
version control
• History stored in a central repository
running on a server
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22. Centralised
version control
• History stored in a central repository
running on a server
• Everyone commits to and from this
repository
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23. Centralised
version control
• History stored in a central repository
running on a server
• Everyone commits to and from this
repository
• Examples: CVS, Subversion (SVN),
Perforce, ClearCase
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24. Distributed
version control
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25. Distributed
version control
• No central server
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26. Distributed
version control
• No central server
• Every team member has a copy of the
entire repository and its history
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27. Distributed
version control
• No central server
• Every team member has a copy of the
entire repository and its history
• Git isn’t the only option — e.g.
Mercurial
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28. Advantages of DVCS
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29. Advantages of DVCS
• Redundancy
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30. Advantages of DVCS
• Redundancy
• Offline working
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31. Advantages of DVCS
• Redundancy
• Offline working
• Speed
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32. Git
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33. Git ≠ GitHub
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34. Terminology, part one
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35. Terminology, part one
• Commit
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36. Terminology, part one
• Commit
• Branch
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37. Terminology, part one
• Commit
• Branch
• Tag
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38. Terminology, part one
• Commit
• Branch
• Tag
• Diff
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39. Terminology, part one
• Commit
• Branch
• Tag
• Diff
• Commitish
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40. Terminology, part two
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41. Terminology, part two
• Pulling
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42. Terminology, part two
• Pulling
• Pushing
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43. Terminology, part two
• Pulling
• Pushing
• Cloning
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44. What’s in a Git commit?
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45. What’s in a Git commit?
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46. What’s in a Git commit?
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47. What’s in a Git commit?
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48. What’s in a Git commit?
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49. Branches
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50. Branches
• In Subversion, they’re basically useless
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51. Branches
• In Subversion, they’re basically useless
• In Git, they’re at the heart of almost
everything
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52. Branches
• In Subversion, they’re basically useless
• In Git, they’re at the heart of almost
everything
• Juggle as many different versions of your
code as you like
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53. Branches
• In Subversion, they’re basically useless
• In Git, they’re at the heart of almost
everything
• Juggle as many different versions of your
code as you like
• Keep all your features nice and separate
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54. Branches
• In Subversion, they’re basically useless
• In Git, they’re at the heart of almost
everything
• Juggle as many different versions of your
code as you like
• Keep all your features nice and separate
• Merge painlessly once you’re done
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55. Special branch
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56. Special branch
• Git doesn’t force you to have any
particular branches
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57. Special branch
• Git doesn’t force you to have any
particular branches
• But by convention, master is your
stable branch
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58. Special branch
• Git doesn’t force you to have any
particular branches
• But by convention, master is your
stable branch
• Branch from it; merge to it; your
releases are taken from it
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59. Branch commands
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60. Branch commands
• git branch foo will create a branch
called “foo”.
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61. Branch commands
• git branch foo will create a branch
called “foo”.
• git checkout bar will switch to the
branch called “bar”
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62. Branch commands
• git branch foo will create a branch
called “foo”.
• git checkout bar will switch to the
branch called “bar”
• git branch -d foo will delete a branch
if you change your mind about it
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63. Merging
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64. Merging
• Once you’re done with a branch, you
can merge it into another:
$ git checkout master
$ git merge --no-ff foo
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65. When should
you branch?
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66. When should
you branch?
• For individual features
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67. When should
you branch?
• For individual features
• What does that mean, though?
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68. When should
you branch?
• For individual features
• What does that mean, though?
• Generally: anything that might be put
live independently
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69. Setting up
a repository
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70. Friday, 23 November 12 22

71. $ git init
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72. Working
with a team
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73. A typical team setup
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74. A typical team setup
You
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75. A typical team setup
You
The rest of the team
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76. A typical team setup
Hub
You
The rest of the team
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77. A typical team setup
Hub
You
Staging
The rest of the team
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78. A typical team setup
Hub
You Production
Staging
The rest of the team
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79. Hooks
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80. Friday, 23 November 12 26

81. • Scripts that run after certain events
— just like actions in WordPress
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82. • Scripts that run after certain events
— just like actions in WordPress
• Potential uses:
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83. • Scripts that run after certain events
— just like actions in WordPress
• Potential uses:
• Post a message in an IRC channel
when someone pushes
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84. • Scripts that run after certain events
— just like actions in WordPress
• Potential uses:
• Post a message in an IRC channel
when someone pushes
• Deploy to the live site when
someone pushes on master
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85. • Scripts that run after certain events
— just like actions in WordPress
• Potential uses:
• Post a message in an IRC channel
when someone pushes
• Deploy to the live site when
someone pushes on master
• Run a syntax checker/strip
whitespace/etc. before commits
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86. Git and WordPress
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87. Things to exclude
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88. Things to exclude
• wp-config.php
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89. Things to exclude
• wp-config.php
• wp-uploads/* (or perhaps not…)
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90. Things to exclude
• wp-config.php
• wp-uploads/* (or perhaps not…)
• Anything that might conceivably be
different on live vs. development
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91. Image uploads
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92. Image uploads
• Image uploads inevitably happen on
live
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93. Image uploads
• Image uploads inevitably happen on
live
• Are they content (so should be
excluded from Git)?
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94. Image uploads
• Image uploads inevitably happen on
live
• Are they content (so should be
excluded from Git)?
• Or are they layout/template related
(so should be included in Git)?
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95. Potential solutions
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96. Potential solutions
• Ignore them — don’t have them in Git at all
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97. Potential solutions
• Ignore them — don’t have them in Git at all
• Periodically add them into Git from the live
server
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98. Potential solutions
• Ignore them — don’t have them in Git at all
• Periodically add them into Git from the live
server
• Automate the adding of them e.g. with a
WordPress hook
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99. Potential solutions
• Ignore them — don’t have them in Git at all
• Periodically add them into Git from the live
server
• Automate the adding of them e.g. with a
WordPress hook
• Which solution depends on the nature of
your images
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100. Plugin/core
upgrades
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101. Plugin/core
upgrades
• If they happen on live, you’ll end up
with untracked files/uncommitted
changes to your live files
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102. Plugin/core
upgrades
• If they happen on live, you’ll end up
with untracked files/uncommitted
changes to your live files
• Doing them on live is insane
regardless, so it makes double sense
to stop doing it
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103. Solutions
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104. Solutions
• Disable upgrades/plugin installs on your live
sites, do upgrades locally, then deploy to live
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105. Solutions
• Disable upgrades/plugin installs on your live
sites, do upgrades locally, then deploy to live
• Remove install_plugins, install_themes,
update_plugins, update_themes, update_core
capabilities from your users on live
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106. Solutions
• Disable upgrades/plugin installs on your live
sites, do upgrades locally, then deploy to live
• Remove install_plugins, install_themes,
update_plugins, update_themes, update_core
capabilities from your users on live
• define('DISALLOW_FILE_EDIT', true); in
your live wp-config.php
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107. Useful resources
• “Think Like a Git”: http://think-like-a-git.net/
• GitRef: http://gitref.org/
• ProGit: http://git-scm.com/book
• Useful Git tips: http://mislav.uniqpath.com/2010/07/git-tips/
• “So, I’ve tried Git” by Ozh http://planetozh.com/blog/2012/11/so-
ive-tried-git-and-its/
• Migrating an SVN repo to Git: http://john.albin.net/git/convert-
subversion-to-git
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108. Git GUIs
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109. Git GUIs
• Use the command line first!
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110. Git GUIs
• Use the command line first!
• But on Windows: Tortoise Git
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111. Git GUIs
• Use the command line first!
• But on Windows: Tortoise Git
• On OS X: Tower, GitBox, Gitti
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112. Git GUIs
• Use the command line first!
• But on Windows: Tortoise Git
• On OS X: Tower, GitBox, Gitti
• On Linux: giggle, gitg, QGit
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113. And finally…
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114. And finally…
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115. And finally…
• Jeff’s leaving! :(
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116. And finally…
• Jeff’s leaving! :(
• We’re hiring! :)
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117. And finally…
• Jeff’s leaving! :(
• We’re hiring! :)
• Apply online:
http://bit.ly/SZJJ8v
or email:
rob@bigfish.co.uk
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